/*
 * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
 * Copyright (c) 2010-2014, Pieter Noordhuis <pcnoordhuis at gmail dot com>
 * Copyright (c) 2015, Matt Stancliff <matt at genges dot com>,
 *                     Jan-Erik Rediger <janerik at fnordig dot com>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of Redis nor the names of its contributors may be used
 *     to endorse or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __HIREDIS_H
#define __HIREDIS_H
#include "read.h"
#include <stdarg.h>   /* for va_list */
#include <sys/time.h> /* for struct timeval */
#include <stdint.h>   /* uintXX_t, etc */
#include "sds.h"      /* for sds */

#define HIREDIS_MAJOR 0
#define HIREDIS_MINOR 14
#define HIREDIS_PATCH 0
#define HIREDIS_SONAME 0.14

/* Connection type can be blocking or non-blocking and is set in the
 * least significant bit of the flags field in redisContext. */
#define REDIS_BLOCK 0x1

/* Connection may be disconnected before being free'd. The second bit
 * in the flags field is set when the context is connected. */
#define REDIS_CONNECTED 0x2

/* The async API might try to disconnect cleanly and flush the output
 * buffer and read all subsequent replies before disconnecting.
 * This flag means no new commands can come in and the connection
 * should be terminated once all replies have been read. */
#define REDIS_DISCONNECTING 0x4

/* Flag specific to the async API which means that the context should be clean
 * up as soon as possible. */
#define REDIS_FREEING 0x8

/* Flag that is set when an async callback is executed. */
#define REDIS_IN_CALLBACK 0x10

/* Flag that is set when the async context has one or more subscriptions. */
#define REDIS_SUBSCRIBED 0x20

/* Flag that is set when monitor mode is active */
#define REDIS_MONITORING 0x40

/* Flag that is set when we should set SO_REUSEADDR before calling bind() */
#define REDIS_REUSEADDR 0x80

#define REDIS_KEEPALIVE_INTERVAL 15 /* seconds */

/* number of times we retry to connect in the case of EADDRNOTAVAIL and
 * SO_REUSEADDR is being used. */
#define REDIS_CONNECT_RETRIES 10

#ifdef __cplusplus
extern "C"
{
#endif

    /* This is the reply object returned by redisCommand() */
    typedef struct redisReply
    {
        int type;                    /* REDIS_REPLY_* */
        long long integer;           /* The integer when type is REDIS_REPLY_INTEGER */
        size_t len;                  /* Length of string */
        char *str;                   /* Used for both REDIS_REPLY_ERROR and REDIS_REPLY_STRING */
        size_t elements;             /* number of elements, for REDIS_REPLY_ARRAY */
        struct redisReply **element; /* elements vector for REDIS_REPLY_ARRAY */
    } redisReply;

    redisReader *redisReaderCreate(void);

    /* Function to free the reply objects hiredis returns by default. */
    void freeReplyObject(void *reply);

    /* Functions to format a command according to the protocol. */
    int redisvFormatCommand(char **target, const char *format, va_list ap);
    int redisFormatCommand(char **target, const char *format, ...);
    int redisFormatCommandArgv(char **target, int argc, const char **argv, const size_t *argvlen);
    int redisFormatSdsCommandArgv(sds *target, int argc, const char **argv, const size_t *argvlen);
    void redisFreeCommand(char *cmd);
    void redisFreeSdsCommand(sds cmd);

    enum redisConnectionType
    {
        REDIS_CONN_TCP,
        REDIS_CONN_UNIX
    };

    /* Context for a connection to Redis */
    typedef struct redisContext
    {
        // 没有发生错误的话， err 会被设置为 REDIS_OK（等于0）。
        int err;          /* Error flags, 0 when there is no error */
        char errstr[128]; /* String representation of error when applicable */
        int fd;
        int flags;
        char *obuf;          /* Write buffer */
        redisReader *reader; /* Protocol reader */

        enum redisConnectionType connection_type;
        struct timeval *timeout;

        struct
        {
            char *host;
            char *source_addr;
            int port;
        } tcp;

        struct
        {
            char *path;
        } unix_sock;

    } redisContext;

    redisContext *redisConnect(const char *ip, int port);
    redisContext *redisConnectWithTimeout(const char *ip, int port, const struct timeval tv);
    redisContext *redisConnectNonBlock(const char *ip, int port);
    redisContext *redisConnectBindNonBlock(const char *ip, int port,
                                           const char *source_addr);
    redisContext *redisConnectBindNonBlockWithReuse(const char *ip, int port,
                                                    const char *source_addr);
    redisContext *redisConnectUnix(const char *path);
    redisContext *redisConnectUnixWithTimeout(const char *path, const struct timeval tv);
    redisContext *redisConnectUnixNonBlock(const char *path);
    redisContext *redisConnectFd(int fd);

    /**
     * Reconnect the given context using the saved information.
     *
     * This re-uses the exact same connect options as in the initial connection.
     * host, ip (or path), timeout and bind address are reused,
     * flags are used unmodified from the existing context.
     *
     * Returns REDIS_OK on successful connect or REDIS_ERR otherwise.
     */
    int redisReconnect(redisContext *c);

    int redisSetTimeout(redisContext *c, const struct timeval tv);
    int redisEnableKeepAlive(redisContext *c);
    void redisFree(redisContext *c);
    int redisFreeKeepFd(redisContext *c);
    int redisBufferRead(redisContext *c);
    int redisBufferWrite(redisContext *c, int *done);

    /* In a blocking context, this function first checks if there are unconsumed
     * replies to return and returns one if so. Otherwise, it flushes the output
     * buffer to the socket and reads until it has a reply. In a non-blocking
     * context, it will return unconsumed replies until there are no more. */
    int redisGetReply(redisContext *c, void **reply);
    int redisGetReplyFromReader(redisContext *c, void **reply);

    /* Write a formatted command to the output buffer. Use these functions in blocking mode
     * to get a pipeline of commands. */
    int redisAppendFormattedCommand(redisContext *c, const char *cmd, size_t len);

    /* Write a command to the output buffer. Use these functions in blocking mode
     * to get a pipeline of commands. */
    int redisvAppendCommand(redisContext *c, const char *format, va_list ap);
    int redisAppendCommand(redisContext *c, const char *format, ...);
    int redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);

    /* Issue a command to Redis. In a blocking context, it is identical to calling
     * redisAppendCommand, followed by redisGetReply. The function will return
     * NULL if there was an error in performing the request, otherwise it will
     * return the reply. In a non-blocking context, it is identical to calling
     * only redisAppendCommand and will always return NULL. */
    void *redisvCommand(redisContext *c, const char *format, va_list ap);
    void *redisCommand(redisContext *c, const char *format, ...);
    void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);

#ifdef __cplusplus
}
#endif

#endif
